Tapping-machine.



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TYAPPING MACHINE.

APPLICATION FILED mutzi. 1911.

1,8U2,271, Patented Apr. 29,1919.

4 SHEETSSHEET '1.

N. H. ANDERSON.

TAPPING MACHINE.

APPLICATION FILED JAN.27.1917.

1,80%;2'71 Patented Apr. 29, 1919.

4 SHEETS-SHEET 2- War/1 N. H. ANDERSON.

TAPPING MACHINE.

APPLICATION man JAN.27.19I7.

1 ,3 11.3 2'? 1 u Patented Apr. 29, 1919.

v 4 SHEETS-SHEET 3.

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low 1% I wuemibz W113i Azzdmm M N. H. ANDERSON.

TAPPING MACHIINE. APPLICATION FILED JAN-27 1911.

Apr. 29, 1919.

4 SHEETS-SHEET 4.

Patented 4 my aw w rr ur c.

TAPPING MACHINE.

Specification of Letters Patent.

Patented am. as, rare.

Application filed January 27, 1917. Serial No. 144,820.

To all whom it may concern:

'Be it known thatI, NILs H. ANDERSON, a citizen of the United States, and resident of Bridgeport, in the county of Fairfield and State ofConnecticut, have invented certain. new and useful Improvements inTapping- Machines, of which the following is a specification. p a

This invention refers to improvements in variable speed tapping machines such as are employed for tapping small holes in relatively light pieces."

The object of the invention is to provide a form of machine for the above purpose having means for securing various speeds for diflerent sizes of taps; also to produce a machine with what is known as an individual electric motor drive, and which will be in every respect a first class machine tool. Another feature of. the invention is to include lubricating means for the tap, so that as it passes through'the work being operated upon it will run into oil. A further feature of the machine is to include a variable speed in which the lengthof time necessary to complete an operation," .that is, the tapping of the piece and the "returning of the tap, will be the same, no matter what speed the spindle may be run in a forward direction, that is, when the tap is entering the work. Another object ofthe invention is to produce what is known as a friction driven tapping machine in which the relative surface speed throughout the width of the effective frictional contact of the driven members is the same as that portion of the surface of the driver engaged by said driven members. 7

The foregoingand other objects of the invention are attained by the mechanism illustrated in the accompanying four sheets of drawings forming a part of this specifica tion, and in the various views of these drawings, like parts are designated by corre sponding characters of reference, and in which-' Figure 1 shows a perspective viewof the machine as it would appear ready for use.

Fig. 2 shows a side elevation of my improved form of machine complete.

Fig. 3 is a central vertical section through the table of the machine taken 011 line '3 of Fig. 4:. I

Fig. 4 shows a front view of the machine as seen in Fig; 2. t i

Fig. 5 is a plan view, the same being illustrated ona somewhat larger scale than the previously described illustrations. I a

Referring in detail to the characters of reference marked upon the drawings 5 represents the main frame which includes a bed portion 6, and arms 7-7 in which the spindle 8 is rotatably mounted. The machine is adapted to be secured toa table or bench 9 of any suitable or preferred construction by means of screws 10. The spindle 8 referred to is mounted to rotate in ball bearings 11 housed in the arms 7 of the frame and inclosed by caps 12 fitted upon the top of the arms and around the spindle. Upon that portion of this spindle arranged between the arms '(-7 are secured, upper and lowerand between the arm I and nuts 17 see Fig.

2 is mounted a spring 18 whichis for the purpose of balancing the weight of the spindle and parts carried thereon so as to make the movement of the spindle upward easily accomplished. This springis made adjustable to regulate its tension upon the spindle 'bythe adjustment of the nuts 17, one of which obviously serves as a lock nut to insure the holding of the lower nut in position when set. The upper end of the spindle, including spring and nuts, are inclosed by a removable cap 19 The sleeves 20'fitted in the upper and lower arms 7, together with the ball bearings, serve to operatablysunport the spindle 9 which is susceptible of a slight endwise movement, as will later be again referred to. i

An electric motor 12 is pivotally mounted at 22 in the two parallel walls of the frame and is adapted to be swung upon its pivots to bring its motor shaft into various angular positions where it is secured bv means of the clamping screw 23 that freely passes through the circular 'slot 24 in the side wall of the frame of the machine and engages the mo"- tor. A spherical faced disk 25 is secured to the motor shaft and serves as the means for transmitting motion from the motor and with which the friction members 13' and 1 1, of the tapping spindle engage.

From the foregoing it willbe evident that if the spindle is lifted will cause the lower friction member 14 to come in contact the central line of the motor shaft and cause the friction member and spindle to be 1-0 tated forward in the direction indicated by -jf On the other hand, if the spindle is drawn down the friction member" the arrow a.

13 will come in contact with the outer face of the driving disk above its center, causing the friction member 13' and the spindle to be rotated in a backward direction as indicated by the arrow 5. Therefore if it should be v 'desiredto change the relative speeds of the friction members 13 and 14 the same could be'acco'mplished by releasing and swinging the motor soas to bring its shaftto a diiferent position, thereby raising or lowering the driving member.

v A bracket 26 having a forwardly extended arm '27 is adjustably secured to the base of the frame. A pair of vertically disposed guide rods QSaresecured in this'arm, and

serve to support the work table 29. 'This work table comprises a top plate that is mounted upon a cylindrical carrier 30 having arms 31 with'alined holes to accommodate the guide rods 28 upon which said arms slide, to raise and lower the table. This cylindrical carrier is hollow forming an oil reservoir, the lower end being closed by means of a plug 32 which is threadably attachedthereto. In: practice this cylinder is filled with oil so that when the tap passes through the work and the hole in the table itiwill-dip into the oil, thus lubricating the end ofthe tap for the next piece of work tobe operated upon. This dip also serves to remove the chips from the end of the tap which might otherwise cause injury while the tap is being returned to its normal posito be-raisedand-lowered to carryand feed the "work'to and-from the'tapf This'table is preferably operated by a flexible foot lever connection as shown inFigs. 1; 2' and 3, andcomprising'an arm 37 that is secured to 'on'e'of the 'guic'leirods 28, and serve to support the lever 38 piv0ted thereto. The

forward end ot this lever engages a shoe iip'onthe under sideof the arm 31 ofthe work table ina'way to raise the same when Y the inner end of the lever 38 isdrawn down.

5A. verticalljg disposed j I 5 pivotedly connected to the inner end of the lever 38.

This rod isa djustably connected to a second vertical"rod40;:the il'ower end of which is pivotedly connected to an arm 41 secured to the pedal rocker shaft 42 mounted in brackets43 and carrying a pedal 44.v

"Loosely mounted on rod 40 is compressiOn spring hl ovhich is held between two collars 46 and 491' This spring serves to give a yielding eonnectionbetween rods 39 and 40 when sucl1-.;yi e l-ding connection is desirable fo'r the proper operation of the machine. ,By tightening screw in block 30 and leaving screw 47 loose, also'tightenin'g screw 48 in'blockor collar"49,*leaving screw 50 loose, themotion from the treadle-mecha- I nism will be transmitted through lever, 41,

rod 40 through the spring 51 to rod 39.

Collar '52 serves to prevent excessive or, lost motion in the return of'the treadle mechanism and the rods to the normal position. This collar is'mounted ion rod 40 adjacent to collar 49 j i 1 In the practical operation of inyimproved tapping machine theoperatorplaces and holds the work to-be tapped upon the table and then operates the pedal 'ina way to raise the table and work to the tap. The engagement 0f the work with thetap causes an upward pressure upon the spindle which brings the* lower friction 'into' engagement with the lower side of the'spherical driving members. This will cause 'the'spindle and tap to run; to the right and through the piece of work. Whenthe-operation is completed the pedal "pressure'fii's released causing the table and spindle to drop slightly and the lower friction to disengage "and the upper one to engage, thus] reversing thedirection of the rotation of" thei'spindle and thereby running theta-p baclovard out of'the work.

From the above" it beiseen that the foregoing construction of machine comprises ea practical form of tapping machine having a great many advantages the main feature being that the time for operation is the same no matterat whatspee'd the tap spindle is rotated in either direction,"th'at is, if the ratio between the driving disk 23 and friction members 13 and 14' is such as to be equal in-both directions and that speed is'2000 R. P; forward'and 2000 R. P. M. reverse. The'motor maybe changed so as to secure 1000 R. P. M. in the forward directio'n, the speed will thenf beincrease'd" in the reverse direction to 3000- RI'P. Misc that the combined figure off4000 maintained.

I Having thus described; my invention" what I claim and-desire to j'seeu're by Letters Patent' is:+ 1

I 1. In a tapping machine of the classf described, the combination of a frame, an electric motor pivotedly mounted'in theframe, a 'spher'ieal unning disk meuntediu en the motor shaft and adapted ,to be raised and lowered by the pivotal adjustment of the motor, means for securing the motor in its adjusted positions, a longitudinally movable tap spindle, a pair of friction members secured thereto and adapted to engage the opposite sides of the spherical disk, a vertically movable Work table, means for raising and lowering the table, and means for yield ably supporting the weight of the table.

2. In a tapping machine of the class described, the combination of a frame, an electric motor pivotedly mounted in the frame, a' spherical driving disk "mounted upon the motor shaft and adapted to be" raised and lowered by the pivotal adjust ment of the motor, means for securing the motor in its adjusted positions, a longitudinally movable tap spindle, a pair of friction members secured thereto and adapted to engage the face of the spherical disk, a spring to balance the spindle, a vertically movable work table, a spring to yieldably support the Weight of the table and means for raising and lowering the table.

3. I11 a tapping machine of the class described, the combination of a frame, an electric motor pivotedly mounted in the frame, a spherical driving disk mounted upon the motor shaft and adapted to be raised and lowered by the pivotal adjustment of the motor, means for securing the motor in its adjusted positions, a. longitudinally movable tap spindle, a pair of friction members secured thereto and adapted to engage the face of the spherical disk, a vertically movable work table having a hole therein, an oil reservoir beneath and carried by the table, means for raising and lowering the table, and means for yieldably supporting the table.

i. In a tapping machine of the class described, the combination of a frame, an electric motor pivotedly mounted in the frame, a spherical driving disk mounted upon the motor shaft and adapted to be raised. and lowered by the pivotal adjustment of the motor, means for securing the motor in its adjusted positions, a longitudinally movable tap spindle, a pair of friction members secured thereto and adapted to engage the face of the spherical disk, on the opposite sides of the axis, a vertically movable work table, a bracket for supporting the table, means for raising and lowering the table, and a spring for yieldably supporting the table.

w 5. A tapping machine of the class de scribed, comprising a main frame, a longitudinally movable tap spindle, a tap carried by said spindle, an electric motor pivotedly mounted in the frame and connected to drive the spindle, a vertically movable work table, meansfor raising and lowering the table, means for moving the tap spindle 'eudu'ise by the pressure of the work on the tap for the purpose of reversing the drive of the tap spindle.

(3. In a tapping machine of the class described, the combination with amain frame, a tap spindle mounted in the frame, a pair of friction members secured to the spindle, an electric motor pivotally mounted in the frame and having a spherical driving disk upon its shaft, said motor being capable of adjustment in the frame to vary the speed of the tap spindle. a

7 In a tappin machine of the class described, the combmation with a main frame, an electric motor pivotally mounted therein and adapted to be adjusted and secured in various positions, a tap spindle, a pair of friction members mounted thereon and hav ing peripheral surfaces to conform to that of the surface of the spherical disk when adjusted to any position and to obtain the maximum drive and efficiency of the machine at all times.

8. The combination in a tapping machine of the class described of a main frame, a vertically disposed and endwise movable spindle mounted therein, a pair of friction members, a chuck suitable for holding a tap mounted on the lower end of said spindle, an electric motor pivotedly mounted in the frame and having a substantially horizontal shaft, a spherically faced disk mounted on said motor spindle adapted to engage the two friction members alternately for the purpose of rotating the tap spindle first in one direction and then in the opposite, a vertically movable work table mounted on suitable slide rods under and adjacent to the tap, means for operating said table by foot treadle mechanism comprising a pair of connection rods, a spring loosely mounted on one of the pair of rods, suitable stop collars for adjusting the spring all and for the purpose described.

9. In a tapping machine. of the class described, the combination of a main frame, an electric motor pivotedly mounted therein, a spherically faced disk mounted on the motor shaft, a vertically disposed tap spindle mounted in the frame, a pair of friction members. mounted on the spindle. a spring loosely mounted on the said vertirally disposed spindle, and means for ad.- justing the tension of said spring to balance the weight of the spindle and asse ciated parts.

10. In a tapping machine of the class described, the combination with a main frame, of an electric motor pivotedly mounted therein, a spherically faced disk mounted on the motor shaft, a tap spindle, a pair of friction members mounted thereon so adjusted as to permit endvvise movement of the spindle for the purpose of alternately engaging and disengaging the frictional members with the spherically faced disk without disturbing the location of said disk.

11, In a tapping machine of the class described, the combination With a main frame, of an electric motor pivotedly mounted therein, a substantially horizontal shaft mounted in the motor, a spherically faced disk mounted on the shaft, a tap spindle having a, pair offriction members mounted thereon so adjusted as to permit endWise movement of the tap spindle for the purpose of alternately engaging and disengaging said friction members and face of spherical disk Without effecting the loca- 1 tionof motor spindle.

Signed at Bridgepont in the county of Fairfield v and State of Connecticut, this 25th day of'January, A. D., 1917.

, V gNILS H. ANDERSON.

Witnesses: l I

C. NEWMAN, RUTH M. W. Koenn.

'flopies' ofthi s patent may be obtained for five cents wonky-addressing the 'j Comniissioner of Patents.

' Washington, D. 0. 

